Harping on About Harpies: Lazuli. Not evil unlike most versions of harpies (a given with the extreme Sugar Bowl nature of the site), but described as "almost as frightening as she is beautiful" nonetheless.

Revenue Enhancing Devices: Various creatures are only available through donation. Bribing Your Way to Victory is avoided, as they don't get achievements so people who can't afford to get one aren't stuck with unfillable lines on the achievements page, and people who can don't get an advantage unlocking stuff that requires a certain number of achievements. Also, missions never require donation pets to access, so donation pets are basically an extra feature with almost no effect on the rest of the site (except that you get a max energy boost for fully evolving them just like every other creature.)

You can also get exotic credits by buying them with the in-game currency of UniCreatures's complementary game, UniFaction. Or you could pray that a ninja comes one day and gives you some. Someone still has to buy the credits to give them to you, though.

This may be the result of a Lighter and Softer transition performed early in the website's run; before that, for example, the Arena was teams of pets fighting instead of sports games (the description for the Moxie Potion still refers to "combat energy",) and the Nagi and Twap families were carnivores.